


The Grey Door

by FireFaceOutlook



Category: Undertale (Video Game)
Genre: M/M, Sans (Undertale) Doesn't Remember Resets, Sanster, W. D. Gaster is not related to Skelebros, Waterfall (Undertale)
Language: English
Status: In-Progress
Published: 2019-08-07
Updated: 2019-08-07
Packaged: 2020-08-11 04:31:04
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
Chapters: 1
Words: 1,081
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/20147671
Author URL: https://archiveofourown.org/users/FireFaceOutlook/pseuds/FireFaceOutlook
Summary: He knocked again.“҉.͏̧͠.̧͡.̸̶̛͘͜.̷̡͢.̵̛̕͢͝.͜͠.͡.̧̛.̨̧͘.̵̴͝.̷̢̧͜.͢͟.̡͜͜.̢̨͢͠.̵.̢̢̢͟͢”̷̶̕ ̛҉̧͞the Void replied, then, like static clearing on a radio,“͘͞.҉̶.͜.͘.̵͢͞.̡̨͝.͟͡ ̨͜҉h̡e̴ll̶̵o̧͝͝?”҉





	The Grey Door

**Author's Note:**

> **A/N: The main reason I'm rewriting this story? I put the grey door in the wrong place. ¯\\_(ツ)_/¯ And, while rereading the two chapters I had written, I feel like I wasn't utilizing all the ammo Undertale has given me to give Gaster all kinds of power in the Void, _and_ there's all kinds of potential for all the mysterious figures outside of the grey door!Gaster (like his followers, the mysterious figure in the True Lab's foggy room, and any other hints of Gaster) to be involved, so... Yeah. Hopefully you guys will like this version better. The first chapter is longer than the original, and it hasn't even had Sans and Gaster have an official conversation!!**

After twenty-odd years of living underground, one would think there wasn't much left to explore of it. It wasn't all that large, despite the thousands of monsters it as home to. By Sans' estimates – estimates he made during his short stint as a scientist –, it would take only a day to cross the Underground's entire length on foot, from the barrier to the beginning of the Ruins, with little wiggle room to linger and stray from the path. (That wiggle room was absolutely important; it meant a few minutes to spare for a nap every hour of travel or so, and everyone knew naps were vital parts of exploration.) Before the Incident that no one mentioned and Sans didn't actually recall the details of, Sans had only ever lived in Hotlands. He single handedly raised Papyrus while still in the stages of growing up himself, went to school and aced college, and landed one of the most prominent jobs in the Underground. Then something went wrong and with a month of his life just a blur of smudged images and distorted sounds, he found himself and his brother living in a conveniently vacated house on the edge of Snowdin Town, as far from Hotlands as they could get with the rumours of the Ruins being permanently sealed.

While Papyrus went about winning the hearts of everyone in town, Sans took to exploring what he'd somehow missed out on during their move. There wasn't actually much to see between Snowdin and the doors to the Ruins. Just snow, trees, snow-covered trees, and even more snow and trees. On the opposite side, however, was Waterfall. One morning, armed with only his wits, a pocketful of spare gold, and his cell phone in case Papyrus needed him, he ventured into the leaky landscape. It was _amazing_. The crystals in the walls and ceiling gave off a glow unlike that of Hotlands' lava or Snowdin's faux sun. It somehow reminded him of the description of stars from an astrology book he had buried amongst his joke books. Aside from the pleasing aesthetics, though, there was plenty to explore in Waterfall: a network of connected caverns with secrets (like an waterlogged piano that still somehow worked, and a weird place called Temmie Village), a snail farm run by two ghost monsters, and a field of Echo Flowers (which Sans _swore_ he'd never seen before, but he knew what they were as soon as he spotted one and listening to the whispers of past monsters made him feel strangely nostalgic). At this point, he decided to call it a day and head home.

He was pretty sure he got turned around at some point while retracing his steps because he found a new cavern where an old rabbit monster and his son were running a nice cream cart. He bought two for the road, smiling at the child's enthusiasm when handing him the treats, and waved goodbye as he returned to the main path. A bit further down it, he came across a hollow carved into the walls – a sight that was becoming more and more common the longer he wandered Waterfall, yet this time it wielded a telescope. He examined the instrument, delighted to find it appeared well-cared for. There was no rust and when he peered into it, he could clearly make out the crystals on the ceiling, some in clusters that mimicked galaxies across the stone. He felt invigorated after a few minutes of amusing himself by creating some constellations (such as the _Legendary Fartmaster_, _The Great Papyrus_, and _Tobius Fox_) and continued along the new way he'd found.

The hallway he entered next had narrowed back down to the usual size of the paths he came into Waterfall through, but as he traveled through it, he found it seemed to be longer and darker than anywhere else he'd been to in Waterfall. He was well on his way to being unsettled enough to find a shortcut to leap through, and that was before he stumbled upon a strange grey door embedded in the wall. A section of him – the same section that he was sure was responsible for his and Papyrus' abrupt relocation – screamed at him to just leave, but the lingering remnants of his scientific side had him reaching for the doorknob. He wasn't sure what he was expecting, but nothing miraculous happened. The doorknob, damp and cold as it was, was just that: a doorknob. The fact that it didn't budge when he tried turning it was curious, however. What came next was almost natural.

He knocked on the door.

  


** _"̛̛͜͠͡.̷̨̧҉.̵͜.̴̶.̛͢͝.̢͡.̛͡.̵̡͢.̷̴̕.҉̷̨.̢҉͏.̴̡̛.̶.̷͜.̴̸͞͞.̢͝.̢͘͟͞.̸̛̕.҉̡̛̕͢.̷̷͢͟.͡͞͏͠.̷͘.̡͝͝.̸̧͡͝.̵̨̢"̢͟͜_ **

  


He wasn't sure what he was expecting to happen, but the disappointment that swelled within him nearly bowled him over. He took a step back to try and assess at what point a possible prank door became so important and nearly jumped out of his skin when the barest trace of a voice came from the other side. He found himself practically plastered against the surprisingly cold wood, inexplicably drawn to the hint of life separated from him by the strange barrier, skull pressed hard against it as he knocked again.

**_“҉.͏̧͠.̧͡.̸̶̛͘͜.̷̡͢.̵̛̕͢͝.͜͠.͡.̧̛.̨̧͘.̵̴͝.̷̢̧͜.͢͟.̡͜͜.̢̨͢͠.̵.̢̢̢͟͢”̷̶̕ ̛҉̧͞ _**the Void replied, then, like static clearing on a radio,**_ “͘͞.҉̶.͜.͘.̵͢͞.̡̨͝.͟͡ ̨͜҉h̡e̴ll̶̵o̧͝͝?”҉_**

Something – some primal, long-forgotten _instinct_ – deep within Sans' soul responded to the unexpected(ly familiar) voice with a myriad of emotions that he couldn't even begin to sort out before he found himself tumbling out of a shortcut and right onto his messily-made bed, soul pounding and feeling as if all the magic had drained from his skull, leaving it heavy and pounding. Hours later, as he absently ate his brother's burnt and watery spaghetti, he was trying to convince himself it wasn't a dream. By the next day, he'd almost completely forgotten about it; what traces he recalled he just brushed aside as a strange dream as he prepared to explore whatever he'd missed out on during his and his brother's move. After all, after twenty-odd years of living underground, wasn't it stranger to _not_ have explored it in its entirety? After all, despite the thousands of monsters it housed, it wasn't all that large.

**Author's Note:**

> **A/N: There you have it. Let me know what you think, if I should continue (I probably will anyway), you can even throw ideas or little easter eggs you might want to see my way! I hope you enjoyed it.**


End file.
